Alcatel-Lucent 6850-48 Reference Guide

Page of 3444
Port Mobility Commands
page 20-4
OmniSwitch CLI Reference Guide
September 2009
vlan dhcp mac range
Defines a DHCP MAC range rule for an existing VLAN. If a DHCP frame contains a source MAC address 
that matches the low or high end MAC or falls within the range defined by the low and high end MAC, the 
frame’s mobile port is temporarily assigned to the rule’s VLAN.
vlan vid dhcp mac range low_mac_address high_mac_address
vlan vid no dhcp mac range low_mac_address
Syntax Definitions
vid
VLAN ID number (1–4094).
low_mac_address
MAC address that defines the low end of the range (e.g., 
00:00:39:59:f1:00). 
high_mac_address
MAC address that defines the high end of the range (e.g., 
00:00:39:59:f1:90).
Defaults
N/A
Platforms Supported
OmniSwitch 6400, 6850, 6855, 9000, 9000E
Usage Guidelines
• Use the no form of this command to delete a DHCP MAC range rule from the specified VLAN. It is 
only necessary to specify the low end MAC to identify which rule to delete; the high end MAC is not 
required.
• Only valid source MAC addresses are allowed for the low and high end boundary MACs. For exam-
ple, multicast addresses (e.g., 01:00:00:c5:09:1a) are ignored even if they fall within a specified MAC 
range. To allow the use of a multicast address as either the low or high end boundary MAC would 
cause misleading DHCP MAC range rule results. 
• Port mobility software checks for and processes DHCP traffic first on an active mobile port. When a 
mobile port receives a DHCP frame that matches a DHCP rule, the port is temporarily assigned to the 
VLAN long enough to forward the DHCP requests within the VLAN broadcast domain. The source 
MAC address of the DHCP frame, however, is not learned for that VLAN port association.
• Once a DHCP device has obtained an IP address, its non-DHCP traffic must match other VLAN rules 
within the same VLAN for the device to remain a member of that VLAN. If this match occurs, then the 
frame source is learned in the matching rule VLAN.
• DHCP rules are most often used in combination with IP network address rules. A DHCP client has an 
IP address of all zeros (0.0.0.0) until it receives an IP address from a DHCP server, so it would not 
match any IP network address rules.